Compressor



June 4, 1963 J. H. HEIDORN COMPRESSOR 4 Sheets-Sheet 2 Filed July 15,1959 w @w MN INVENTOR. John H. Heidorn BY J H13 A T70R35 Y J. H. HEIDORNJune 4, 1963 COMPRESSOR 4 Sheets-Sheet I5 Filed July 15, 1959 INVENTOR.H. Hex dam HIS ATTORNEY J. H. HEIDORN June 4, 1963 COMPRESSOR 4Sheets-Sheet 4 INVENTOR. John H. Heza'orn BY g H15 AT oR/v y UnitedStates Patent Ofilice 3,092,307 Patented June 4, 1963 339L367 CGNPRESORSohn H. Heidorn, Bayton, Ghio, assignor to General Motors Qorporation,Detroit, liiicin, a corporation of Deltaware Filed .luly 15, 1959, Ser.No. 827,346 2 Qim'ms. (Ql. 23d2}6) This invention relates torefrigerating apparatus and more particularly to a refrigerantcompressor for use in automobile air conditioning systems and the like.

A large number of problems present themselves in designing refrigerantcompressors of the type which are adapted to be driven by a car engineeither continuously or intermittently through a clutch. These problemsresult from the fact that the compressor is required to operatethroughout a very wide speed range wherein the speed of the compressorbears no relationship to the refrigeration requirements. The problemsare multiplied by the fact that the amount of space available for thecompressor is very limited and all of the parts must be of lightweightconstruction and arranged in a small casmg.

It is an object of this invention to provide a compressor for use in airconditioning automobiles wherein the compressor occupies a minimumamount of space.

Another object of this invention is to provide a compressor which isadapted to be driven from a car engine through an improved clutcharrangement.

A further object of this invention is to provide improved means forinsuring an adequate supply of lubricant to the moving parts in a highspeed compressor.

Further objects and advantages of the present invention will be apparentfrom the following description, reference being had to the accompanyingdrawings wherein preferred embodiments of the present invention areclearly shown.

In the drawings:

FIGURE 1 is a vertical sectional view showing a preferred form of theinvention.

FIGURE 2 is a sectional view taken substantially on line 2-2 of FIGURE 1with parts broken away.

FIGURE 3 is a sectional view taken substantially on line 3-3 of FIGURE 1looking in the direction of the arrows.

FEGURE 4 is a fragmentary sectional view showing the relationship of theoil pump housing to the drive shaft of the compressor.

FIGURE 5 is a sectional view taken on line 55 of FIGURE 1 and looking inthe direction of the arrows.

FIGURE 6 is a sectional view showing a modified type of compressor.

FIGURE 7 is a sectional view taken substantially on line 77 of FIGURE 6and looking in the direction of the arrows.

FIGURE 8 is a fragmentary sectional view showing the clutch in the earlystages of engagement.

FEGURE 9 is a view similar to FIGURE 8 but showing the clutch fullyengaged.

Referring now to FIGURE 1 of the drawings wherein a preferred embodimentof the invention has been shown, reference numerals it and 12 designatecomplementary cup-shaped casing elements which serve to enclose amultiple cylinder compressor. These casing elements are made of sheetmetal and have their open ends arranged in telescoping relationship, asbest shown in FIGURE 1.

The compressor consists of a cylinder block 14 which is supported withinthe casing element 12 and which is provided with four cylinder bores 16which are symmetrically arranged about the main drive shaft 18. Byvirtue of using four cylinder bores arranged as shown, it is possible toutilize an outer casing which is substantially rectangular in crosssection rather than using a cylindrical casing of the type most commonlyused in automobile air conditioning compressors. This makes it possibleto reduce the width and height of the compressor casing without reducingthe capacity of the compressor.

Reciprocating piston elements 20 are disposed to operate within thebores 16 in accordance with conventional practice. These piston elementsare driven by the wobble plate assembly 22 through the usual conectingrods 24. The gas to be compressed enters through the usual suction line28 which communicates with the low pressure suction chamber 36 formed inthe cylinder head 32. The usual valve plate 34 is disposed between thecylinder head 32 and the cylinder block 14 and is provided with theusual series of inlet and outlet ports 36 and respectively. Thecompressed gas leaves the compressor through the outlet passage 4%.

As 'best shown in FIGURES l and 3 of the drawings, the outlet valve reed42 is circular in shape and has its central portion clamped firmly tothe valve plate 34 by means of a cap screw 44. The extent of opening ofthe reed valve 42 is limited by a rigid backup plate member 46. Thevalve plate 42 is provided with cutaway portions 48 which render it moreflexible and in effect divide the reed into four lobes which are tiedtogether at their outer periphery. The backup plate 46, as shown in FIG-URE 3, is provided with lobes which overlie the outlet ports 38. Byconstructing the reed valve in the form of a single platelike element,the severity of the opening and closing movement of the valve plate isreduced since the compressed gas flowing out of the one outlet port at agiven time tends to retard the closing movement of the next precedingvalve port and also tends to initiate the opening movement of the nextsucceeding valve port.

The main drive shaft 18 is supported for rotation within the casingsection 10 by means of a first ball bearing assembly 59 in which theinner ball race 51 is secured to the shaft 18 and the outer ball race 54is carried by the end wall of the casing 10. This first ball bearingassembly serves to take up the end thrust resulting from the wobbleplate pushing against the piston elements. A second ball bearingassembly 52 is provided as shown and serves to take up the belt load.This second ball bearing assembly is arranged directly in line with thebelts 55 which drive the compressor pulley 56 secured to the outer ballrace of the ball bearing assembly 52. It will be noted that the member54 which forms the outer ball race for the bearing assembly 5% alsoforms the inner ball race of the ball bearing assembly 52 and is, ineffect, an extension of the stationary housing element 10. By virtue ofthis bearing arrangement, the ball bearings and the associated ballraces stand up much longer in service than the prior art arrangements asthe bearing assembly 52 takes the main belt load and the balls arealways moving about in the races whenever the car engine operates.

The inner end of the drive shaft 18 is journaled in the cylinder block14 in such a manner that slight misalignment between the casing sections10 and 12 will not cause excessive strain or wear on the drive shaft 18.As best shown in FIGURES 1 and 4 of the drawings, the inner end of thedrive shaft extends into a tapered opening (shown somewhat exaggeratedin FIGURE 4) in a member 66 which is adapted to rotate with the shaft18. As show-n in FIGURE 2 of the drawings, the shaft 18 is provided witha fiat portion 62 which cooperates with a fiat portion on the member 69so that the member 60 rotates with the shaft 18 but due to the taper onthe inner surface of the member 69, the shaft 18 need not line upexactly with the opening in the member 60.

The one end of the member 60 is provided with an oil pumping chamber 64.The inner walls of the oil pumping chamber 64 are provided withconventional gear teeth projections 66 which cooperate with conventionaloil pumping gear 68 rotatably supported on a fixed pin 70. Thus, thegear element 68 in cooperation with the rotating member 60 serves toform a gear type oil pump which supplies oil under pressure to thevarious bearings requiring lubrication.

Referring now to FIGURE 1 of the drawings, the bottom portion of thecompressor casing serves as an oil sump and oil from this sump is pumpedupwardly through the oil passage 72 to the inlet side of the oil pumpjust described. The oil discharges from the pumpinto a chamber 74 whichcommunicates with oil passage means 76 and 78 provided in the pin 70 andin the main shaft 18. The oil is then fed through the radial passage 79to the wobble plate bearings.

A coil spring 80 serves to bias the member 60 to the left as viewed inFIGURE 1. However, if the speed of the compressor should become greatenough so that the quantity of oil handled by the pump exceeds theamount of oil which can flow through the oil feed passage '78, theexcessive oil pressure in the pumping chamber will cause the elements 60and the oil pump gear 68 to move to the right, as viewed in FIGURE 1, soas to automatically unload the oil pump.

When no refrigeration is required; the compressor may be declutched fromthe car engine and the drive pulley.

56 by means of the magnetic clutch shown in FIGURES l and 5. This clutchincludes a solenoid 90 embedded in the pulley 56, as shown. Current issupplied to the solenoid 90 by means of a collector ring 92 cooperatingwith a brush element 94 carried by the fixed casing element 10. Thesolenoid coil 99 is adapted when energized to pull the armature element96 into frictional engagement with the surface 98 provided on the pulley56. The one side of the solenoid 90 is grounded to the pulley 56 and inorder to insure proper electrical connection between the pulley assemblyand the rest of the compressor, a spring pressed ground contact 91 isprovided, as shown, for at all times making electrical connectionbetween the housing 108 of the pulley assembly and the shaft 18.

When the armature 96 first contacts the surface 98 in response toenergization of the solenoid 90, the armature 96 will tend to rotatewith the pulley 56 with the result that a series of conventionalspreader balls 100 will serve to force the clutch plate 102 to theright, as viewed in FIGURE 1, so that the friction material 104 carriedby the clutch plate 102 will engage-the clutch surface 106 formed on theclutch enclosing casing element 108. The element 108 is secured to thepulley 56 so as to rotate therewith. A plate element 110 which is keyedto the drive shaft 18 is arranged between the armature 96 and the clutchplate 102. This plate element is secured to the clutch plate 102 througha plurality of arcuate spring members 112, as best shown in FIGURE 5.One end of each of the spring arms 112 is secured to the plate 110 bymeans of a rivet 114 and the other end of each of the spring arms issecured to the plate 102 by means of rivets 116.

A conventional oil seal assembly 120 is provided for preventing theescape of lubricant and refrigerant at the point where the drive shaft18 passes through the end wall of the casing 10. Suitable O-1ing seals122 are provided, as shown, for preventing the leakage of gas betweenvarious parts of the compressor elements.

In FIGURE 6 of the drawings, a modified form of the invention is shown.'Like reference numbers have been used in FIGURES l and 6 to designateidentical parts or parts which are similar in function. In themodification shown in FIGURE 6, a plain end thrust bearing 200 isprovided for the drive shaft 18. The main drive pulley 202 is rotatablysupported on the compressor housing by means of a ball bearing assembly204 which 4 is directly in line with the drive belts 55 so as to take upthe belt load. The clutch for operating the compressor dilfers from theclutch construction described hereinabove in that in place of using aclutch of the type wherein the clutch surfaces are mechanically held inengagement and the solenoid is merely used to initiate the operation ofthe clutch, the arrangement shown in FIGURE 6 utilizes a clutch of thetype in which the solenoid coil 206 holds the clutch in engagement. Inthe arrangementshown, the solenoid coil 206 which corresponds to thesolenoid of FIGURE 1 is arranged in a circular groove 208 formed in theouter face of the pulley 202. Suitable nonmagnetic material 210 servesto hold the solenoid 206 in place and also serves to support an armaturering 212 which is arranged as shown. Keyed to the shaft 18 is anarmature supporting plate assembly 214 which is held in place on theshaft 18 by means of a nut 215. The plate assembly 214 carries a firstringlike armature'element 216 and a second ringlike armature element218. The armature supporting plate assembly comprises a rigid plate 230carried by the shaft 18 and a flexible armature supporting plate 232 towhich the armature rings 216 and 218 are secured by means of rivets 234.Arm like projections 236 formed on the plate 232 and having theirextremities secured to the rigid plate 230 by means of rivets 238 enablethe armature rings 216 and 218 to move into and out of engagement withthe complementary clutch surfaces. The armature ring element 216 isslightly thicker than the element 218 with the result that when thesolenoid 206 is first energized, the armature element 216 will move intocontact with the surfaces 220 and 222 explanation of the principle ofoperation thereof.

While the embodiments of the present invention as herein disclosed,constitute preferred forms, it is to be understood that other formsmight be adopted.

What is claimed is as follows:

1. In a compressor, a casing, a cylinder block supported in said casing,said cylinder block having a bearing aperture and a plurality ofcylinder bores formed therein, piston means operable in said cylinderbores, a drive shaft having its one end journalled in one Wall of saidcasing, a wobble plate assembly carried by said shaft for actuating saidpiston means, a self-aligning bearing connection between said shaft andsaid cylinder block, said self-aligning bearing connection comprising asleeve loosely surrounding the end of said shaft and disposed betweenthe end of the shaft and said cylinder block, said sleeve having ahollow end portion projecting beyond the end of said shaft and providedwith internal gear teeth, a complementary oil pumping gear disposedwithin said hollow end portion and cooperating with said gear teeth toform an oil pumping chamber, means forming inlet and outlet ports forsaid oil pumping chamber, and

a fixed pivot pin carried by said cylinder block and extending into thecentral portion of said pumping gear.

2. In a compressor, a casing, a cylinder block supported in said casing,said cylinder block having a bearing aperture and a plurality ofcylinder bores formed therein, piston means operable in said cylinderbores, a drive shaft having its one end journalled in one wall of saidcasing, a wobble plate assembly carried by said shaft for actuating saidpiston means, a self-aligning bearing connection between said shaft andsaid cylinder block, said selfaligning bearing connection comprising asleeve loosely surrounding the end of said shaft and disposed betweenthe end of the shaft and said cylinder block, said sleeve having ahollow end portion projecting beyond the end of said shaft and providedWith internal gear teeth, a complementary oil pumping gear disposedwithin said hollow end portion and cooperating with said gear teeth toform an oil pumping chamber, means forming inlet and outlet ports forsaid oil pumping chamber, spring means biasing said bearing sleeverelative to said pumping gear whereby said pumping gear is releasablyheld in said hollow end portion, and a fixed pivot pin carried by saidcylinder block and extending into the central portion of said pumpinggear.

References Cited in the file of this patent UNITED STATES PATENTS598,678 Olin Feb. 8, 1898 6 Richards May 29, Wemp Oct. 30, Hewitt et a1.Mar. 11, Doebeli Nov. 10, Steinhagen et a1 May 29, Carr July 15, DolzaJan. 13, Niekerson June 30, Jacobs Oct. 6, Purcell Nov. 24, Zeidler Nov.24, vBuczich Sept, 20,

FOREIGN PATENTS Canada July 31,

1. IN A COMPRESSOR, A CASING, SAID CYLINDER BLOCK SUPPORTED IN SAIDCASING, SAID CYLINDER BLOCK HAVING A BEARING APERTURE AND A PLURALITY OFCYLINDER BORES FORMED THEREIN, PISTON MEANS OPERABLE IN SAID CYLINDERBORES, A DRIVE SHAFT HAVING ITS ONE END JOURNALLED IN ONE WALL OF SAIDCASING, A WOBBLE PLATE ASSEMBLY CARRIED BY SAID SHAFT FOR ACTUATING SAIDPISTON MEANS, A SELF-ALIGNING BEARING CONNECTION BETWEEN SAID SHAFT ANDSAID CYLINGDER BLOCK, SAID SELF-ALIGNING BEARING CONNECTION COMPRISING ASLEEVE LOOSELY SURROUNGING THE END OF SAID SHAFT AND DISPOSED BETWEENTHE END OF THE SHAFT AND SAID CYLINDER BLOCK, SAID SLEEVE HAVING AHOLLOW END PORTION PROJECTING BEYOND THE END OF SAID SHAFT AND PROVIDEDWITH INTERNAL GEAR TEETH, A COMPLEMENTARY OIL PUMPING GEAR DISPOSEDWITHIN SAID HOLLOW END PORTION AND COOPERATING WITH SAID GEAR TEETH TOFORM AN OIL PUMPING CHAMBER, MEANS FORMING INLET AND OUTLET PORTS FORSAID OIL PUMPING CHAMBER, AND A FIXED PIVOT PIN CARRIED BY SAID CYLINDERBLOCK AND EXTENDING INTO THE CENTRAL PORTION OF SAID PUMPING GEAR.